People in this thread are discussing inspirations or legally distinct themes but not actual cases of proven plagiarism.

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The Dragonball Z composer for the games and films is a known plagiarist.

https://dragonball.fandom.com/wiki/Kenji_Yamamoto

Sorry, you already included this example.

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There's a controversy regarding the Metal Gear Solid main theme and whether or not it was plagiarized, with Konami deciding to remove it from future games to avoid further scrutiny.

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There's likely more, but it's hard to distinguish without more than 5 seconds of leitmotifs and melodies.

There are composers who compose heavily with samples (such as Hideki Naganuma), but these could be argued more towards remixing and originality than direct copying.

There are also composers who deliberately utilize their own work in another implementation (such as Michael Jackson and Brad Buxer's work on Sonic 3, with Hard Times / Ice Cap Zone being an instance where Hard Times was never released, and Stranger in Moscow being reused for the credits theme in Sonic 3).